//javascript Document
function chinaz() {
	this.init();
}
chinaz.prototype = {
	constructor : chinaz,
	init : function() {
		this._initBackTop();
	},
	_initBackTop : function() {
		var $backTop = this.$backTop = $('<div class="cbbfixed">'
				+ '<a class="gotop cbbtn">' + '<span class="up-icon"></span>'
				+ '</a>' + '<a class="cweixin cbbtn"">'
				+ '<span class="weixin-icon"></span><div></div>' + '</a>' +

				'</div>');
		$('body').append($backTop);

		$backTop.click(function() {
			$("html, body").animate({
				scrollTop : 0
			}, 120);
		});

		var timmer = null;
		$(window).bind(
				"scroll",
				function() {
					var d = $(document).scrollTop(), e = $(window).height();
					0 < d ? $backTop.css("bottom", "10px") : $backTop.css(
							"bottom", "-90px");
					clearTimeout(timmer);
					timmer = setTimeout(function() {
						clearTimeout(timmer)
					}, 100);
				});
	}

}
var chinaz = new chinaz();